/*
 *  eXist Open Source Native XML Database
 *  Copyright (C) 2001-04 The eXist Project
 *  http://exist-db.org
 *  
 *  This program is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU Lesser General Public License
 *  as published by the Free Software Foundation; either version 2
 *  of the License, or (at your option) any later version.
 *  
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU Lesser General Public License for more details.
 *  
 *  You should have received a copy of the GNU Lesser General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *  
 *  $Id$
 */
package org.exist.xquery.pragmas;

import org.exist.xquery.*;
import org.apache.log4j.Logger;
import org.exist.Namespaces;
import org.exist.dom.QName;
import org.exist.xquery.util.ExpressionDumper;

public class TimerPragma extends Pragma {

    public  final static QName TIMER_PRAGMA = new QName("timer", Namespaces.EXIST_NS, "exist");
    
    private Logger log = null;
    
    private long start;
    private boolean verbose = true;

    public TimerPragma(QName qname, String contents) throws XPathException {
        super(qname, contents);
        if (contents != null && contents.length() > 0) {
            String options[] = Option.tokenize(contents);
            for (int i = 0; i < options.length; i++) {
                String param[] = Option.parseKeyValuePair(options[i]);
                if (param == null)
                    throw new XPathException("Invalid content found for pragma " + TIMER_PRAGMA.getStringValue() +
                        ": " + contents);
                if ("verbose".equals(param[0])) {
                    verbose = "yes".equals(param[1]);
                } else if ("logger".equals(param[0])) {
                    log = Logger.getLogger(param[1]);
                }
            }
        }
        if (log == null)
            log = Logger.getLogger(TimerPragma.class);
    }

    public void after(XQueryContext context, Expression expression) throws XPathException {
        long elapsed = System.currentTimeMillis() - start;
        if (log.isTraceEnabled()) {
            if (verbose)
                log.trace("Elapsed: " + elapsed + "ms. for expression:\n" + ExpressionDumper.dump(expression));
            else
                log.trace("Elapsed: " + elapsed + "ms.");
        }
    }

    public void before(XQueryContext context, Expression expression) throws XPathException {
        start = System.currentTimeMillis();
    }
}